阅读说明：本技术 一种用于氯代烃污染物高效增溶的阴离子型Gemini表面活性剂及其合成方法 (Anionic Gemini surfactant for efficiently solubilizing chlorinated hydrocarbon pollutants and synthesis method thereof ) 是由 董军 梁雪 杨朝格 徐非凡 蔡培垚 莫言阳 姜迪瀚 于 2019-10-17 设计创作，主要内容包括：本发明涉及一种用于氯代烃污染物高效增溶的阴离子型Gemini表面活性剂及其合成方法,合成的乙二醇双马来酸正癸醇双酯磺酸盐Gemini表面活性剂(GS-10)溶于水后在浓度高于临界胶束浓度条件下形成带负电的胶束,疏水性氯代烃如TCE、PCE进入胶束从而使水中污染物表观溶解度增大；本发明可以优选的用于地下水表面活性剂原位冲洗技术修复含水层中残余态氯代烃污染物,应用广泛。(The invention relates to an anionic Gemini surfactant for efficiently solubilizing chlorinated hydrocarbon pollutants and a synthesis method thereof.A synthesized ethylene glycol dimaleate n-decyl alcohol diester sulfonate Gemini surfactant (GS-10) forms negatively charged micelles under the condition that the concentration is higher than the critical micelle concentration after being dissolved in water, and hydrophobic chlorinated hydrocarbons such as TCE and PCE enter the micelles so as to increase the apparent solubility of the pollutants in the water; the method can be preferably used for repairing the residual chlorinated hydrocarbon pollutants in the aquifer by using the underground water surfactant in-situ washing technology, and has wide application.)

1. An anionic Gemini surfactant for efficiently solubilizing chlorinated hydrocarbon pollutants, which is characterized in that:

A. adding a spacer: the esterification reaction of maleic anhydride and glycol under the catalysis of p-toluenesulfonic acid generates an intermediate product of ethylene glycol dimaleate monoester;

B. adding a hydrophobic chain: ethylene glycol dimaleate monoester and n-decyl alcohol are subjected to esterification reaction under the catalysis of vacuum nitrogen and p-toluenesulfonic acid to produce an intermediate product ethylene glycol dimaleate n-decyl alcohol diester;

C. adding a hydrophilic group: adjusting the pH value of the intermediate product ethylene glycol dimaleate n-decyl alcohol diester to be neutral by using a sodium hydroxide solution, adding a sodium bisulfite solution for sulfonation reaction to obtain a product, and drying at 105 ℃ to obtain a final product, namely a white solid ethylene glycol dimaleate n-decyl alcohol sulfonate Gemini surfactant;

wherein the structural formula of the anionic Gemini surfactant is as follows:

2. the anionic Gemini surfactant for efficient solubilization of chlorinated hydrocarbon contaminants of claim 1, wherein: and step A, the reaction temperature is 70 ℃, the molar ratio of maleic anhydride to ethylene glycol is 2.05:1, acetone is used as a solvent, and the reaction time is 1 hour.

3. The anionic Gemini surfactant for efficient solubilization of chlorinated hydrocarbon contaminants of claim 1, wherein: and step B, the reaction temperature is 120 ℃, the molar ratio of the maleic anhydride to the n-decanol is 1.15:1, and the reaction time is 3 hours.

4. The anionic Gemini surfactant for efficient solubilization of chlorinated hydrocarbon contaminants of claim 1, wherein: and step C, the reaction temperature is 110 ℃, the molar ratio of the maleic anhydride to the sodium bisulfite is 1.05:1, and the reaction time is 8 hours.

Technical Field

The invention belongs to the technical field of surfactants, and particularly relates to an in-situ surfactant, in particular to an anionic Gemini surfactant with high-efficiency solubilizing capability on chlorohydrocarbon pollutants and a synthesis method thereof.

Background

Underground water is a main source of drinking water in China, and the problem of organic pollution of the underground water is more and more serious along with the development of industry and agriculture. Chlorinated hydrocarbons are widely used as degreasing agents, cleaning agents and intermediates in industrial synthesis, and therefore the detection rate of chlorinated hydrocarbon pollutants in groundwater investigation around the world is extremely high. Most chlorinated hydrocarbons such as Trichloroethylene (TCE) and tetrachloroethylene (PCE) have a density higher than water, low solubility in water, high toxicity and are not easily degraded, and belong to heavy non-aqueous liquids (DNAPLS). Such contaminants migrate by gravity to the aquifer upon entering the subterranean environment and become trapped in the aquifer medium.

The extraction-treatment technique is the most commonly used technique for repairing the organic polluted site, which can effectively remove the chlorinated hydrocarbon pollutants in the free phase in the aquifer, but can not remove the residual chlorinated hydrocarbon trapped and adsorbed in the medium, thereby generating the phenomena of tailing and rebound. Therefore, after using extraction-treatment techniques in the field, surfactant flushing techniques are often used for residual chlorinated hydrocarbon contaminants in underground aquifers, surfactant solutions are injected into the contaminated underground aquifers, underground water and leachates are extracted downstream of the zone of contamination, and the surfactant solutions remove the residual chlorinated hydrocarbon contaminants by increasing the solubility of the chlorinated hydrocarbon in the water.

In the existing research and engineering repair, nonionic and anionic surfactants are often selected as flushing agents, such as tween 80, triton 100, Sodium Dodecyl Sulfate (SDS) and the like. However, the existing surfactants have certain defects in repair, such as excellent solubilizing effect of the nonionic surfactant, but the formed micelle is electroneutral, so that the formed micelle has larger adsorption loss in an electronegative underground aquifer; the anionic surfactant has less absorption loss in the underground aquifer, but needs higher dosage to achieve better solubilization effect due to higher critical micelle concentration. Thus, surfactants that have a high solubilizing power while not being readily adsorbed onto the aqueous medium are more suitable for use in surfactant in situ rinse techniques.

The Gemini type surfactant is a novel surfactant formed by linking two amphiphilic molecules through a linking group. Compared with the traditional surfactant with only 1 hydrophilic group and 1 lipophilic group in the molecular structure, the Gemini type surfactant has 2 hydrophilic groups and 2 lipophilic groups in the molecular structure, wherein two monomers are connected by chemical bonds, so that the repulsive force at the base end of an ion head is greatly weakened. The Gemini type surfactant molecules can be tightly arranged in the interface or molecular aggregate under the action, so that the surface tension is effectively reduced, and the critical micelle concentration of the Gemini type surfactant is lower than that of the traditional surfactant. The Gemini type surfactant forms an internal hydrophobic micelle in water when the concentration of the internal hydrophobic micelle is higher than the critical micelle concentration after being dissolved in the water, and when the aqueous solution of the Gemini type surfactant is injected into an aqueous layer containing residual state hydrophobic chlorohydrocarbon pollutants, the hydrophobic chlorohydrocarbon enters the inside of the micelle so as to improve the dissolving amount of the hydrophobic chlorohydrocarbon in the water and realize solubilization. The hydrophobic chlorinated hydrocarbons encapsulated by the micelles can flow and transport with the aqueous solution like a dissolved phase, thereby flushing residual chlorinated hydrocarbon contaminants from the aqueous layer.

At present, related patents and reports have appeared on the research and preparation of sulfonate anionic Gemini surfactants, and a patent CN105435706 discloses a sulfonate anionic Gemini surfactant with a linked chain containing an ether oxygen bond, which is prepared by taking hydroquinone, bromoalkane, dibromoalkane (or dibromo polyglycol) and chlorosulfonic acid as raw materials and carrying out three steps of a two-step substitution reaction and a sulfonation reaction. Patent CN101554569 discloses an anionic Gemini surfactant and a synthesis method thereof, wherein a series of anionic Gemini surfactants are synthesized by using fatty acid and chlorosulfonic acid as raw materials and using ethylenediamine as a spacer group. However, the synthetic materials in the above patents take a long time, chlorosulfonic acid is used as a sulfonating agent in the sulfonation step, chlorosulfonic acid is a dangerous material which may explode when meeting moisture, the sealing performance is required during the synthetic operation, and there is a certain risk. Meanwhile, the currently reported sulfonate anionic Gemini surfactant mainly focuses on improving the purity and researching the basic property of the surface tension of a product, the solubilization effect is not researched, and the surfactant is mainly used for oil displacement in the field of oil exploitation and is not applied to repairing the pollution of hydrophobic chlorohydrocarbon in an underground water-bearing stratum. Therefore, a preparation method which is shorter in time consumption and simpler, more convenient and safer in operation process is found, and the method has more practical application significance in researching the performance of the product aiming at the characteristics of practical application environment.

Disclosure of Invention

The invention aims to provide an anionic Gemini surfactant for efficiently solubilizing chlorinated hydrocarbon pollutants and a synthesis method thereof aiming at the electronegativity characteristic of an underground environment, the anionic Gemini surfactant is suitable for flushing and repairing residual hydrophobic chlorinated hydrocarbon pollutants in an underground water-containing layer, the synthesized ethylene glycol dimaleate n-decyl alcohol diester sulfonate Gemini surfactant (GS-10) forms negatively charged micelles after being dissolved in water under the condition that the concentration is higher than the critical micelle concentration, and hydrophobic chlorinated hydrocarbons such as TCE and PCE enter the micelles to increase the apparent solubility of the pollutants in the water.

The purpose of the invention is realized by the following technical scheme:

an anionic Gemini surfactant for efficient solubilization of chlorinated hydrocarbon contaminants, having the following structural formula:

the preparation method of the anionic Gemini surfactant for efficiently solubilizing the chlorinated hydrocarbon pollutants comprises the following steps:

A. adding a spacer: the esterification reaction of maleic anhydride and glycol under the catalysis of p-toluenesulfonic acid generates an intermediate product of ethylene glycol dimaleate monoester;

B. adding a hydrophobic chain: ethylene glycol dimaleate monoester and n-decyl alcohol are subjected to esterification reaction under the catalysis of vacuum nitrogen and p-toluenesulfonic acid to produce an intermediate product ethylene glycol dimaleate n-decyl alcohol diester;

C. adding a hydrophilic group: adjusting the pH value of the intermediate product ethylene glycol dimaleate n-decyl alcohol diester to be neutral by using a sodium hydroxide solution, adding a sodium bisulfite solution for sulfonation reaction to obtain a product, and drying at 105 ℃ to obtain a final product, namely a white solid ethylene glycol dimaleate n-decyl alcohol diester sulfonate Gemini surfactant (GS-10).

And step A, the reaction temperature is 70 ℃, the molar ratio of maleic anhydride to ethylene glycol is 2.05:1, acetone is used as a solvent, and the reaction time is 1 hour.

And step B, the reaction temperature is 120 ℃, the molar ratio of the maleic anhydride to the n-decanol is 1.15:1, and the reaction time is 3 hours.

And step C, the reaction temperature is 110 ℃, the molar ratio of the maleic anhydride to the sodium bisulfite is 1.05:1, and the reaction time is 8 hours.

Compared with the prior art, the invention has the beneficial effects that:

1. the synthetic raw materials of the GS-10 have wide sources, low price, greenness and low toxicity, the operation is safe and simple, the reaction time is short, and the conditions are mild;

2. after the GS-10 is dissolved in water, the Critical Micelle Concentration (CMC) is very small and is lower than that of the traditional anionic surfactant such as SDS, so that the surface tension of the aqueous solution can be effectively reduced;

3. the micelle formed in the GS-10 aqueous solution is negatively charged, so that the migration of a surfactant material in an aqueous layer medium is facilitated;

4. after being dissolved in water, the GS-10 can form an internal hydrophobic micelle when being higher than CMC, so that the solubility of hydrophobic chlorohydrocarbon pollutants such as Trichloroethylene (TCE) and tetrachloroethylene (PCE) in water is increased, and the solubilizing quantity is increased along with the increase of the concentration of a surfactant;

5. the solubilization capacity of the GS-10 aqueous solution to chlorohydrocarbon pollutants such as TCE and PCE is superior to that of traditional surfactants such as Sodium Dodecyl Sulfate (SDS), triton 100 and Tween 80 with the same mass concentration under the condition of lower mass concentration such as 10g/L, and the solubilization capacity to PCE in a soil column washing experiment can reach about 40 times of that in water;

6. the method can be preferably used for repairing the residual chlorinated hydrocarbon pollutants in the aquifer by using the underground water surfactant in-situ washing technology, and has wide application.

Drawings

FIG. 1 is an infrared spectrum of an anionic Gemini surfactant according to an embodiment of the present invention;

FIG. 2 is a graph showing the change of surface tension of aqueous solutions of a series of concentrations of anionic Gemini surfactant according to an embodiment of the present invention;

FIG. 3 is a Zeta potential result chart of aqueous solutions of anionic Gemini surfactants series concentration according to the embodiment of the present invention;

FIG. 4 is a graph showing the solubilizing effect of anionic Gemini surfactants and conventional surfactants on TCE according to an embodiment of the present invention;

FIG. 5 is a graph illustrating the solubilizing effect of anionic Gemini surfactants and conventional surfactants on PCE according to an embodiment of the present invention;

FIG. 6 is a graph showing the solubilization effect of 10g/L anionic Gemini surfactant and PCE in a column washed with clean water.

Detailed Description